Dry cleaning machine with a refrigeration system adopted for multiple solvents

ABSTRACT

A dry cleaning machine with washing and drying cycles and a refrigeration system has a rotary drum holding clothing or likes, a first solvent tank for storing a first solvent for a first washing cycle, a second solvent tank storing a second solvent for a second washing cycle, a first water separator operationally connected to the first solvent tank, a second water separator operationally connected to the second solvent tank, and a solvent recovery system operationally connected to the first and second water separators at one end and the rotary d The refrigeration system contains a first heat exchange system, a second heat exchange system, a refrigeration tank storing a refrigerant, and a fan for cooling the refrigerant. The dry cleaning machine is configured so that the different solvents can he independently used within the same machine for different washing cycles without need of manual exchange of the solvents or system purge.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(e)to U.S. provisional application No. 61/664750, entitled “A Dry CleaningMachine” filed on Jun. 27, 2012, the contents of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates generally to a dry cleaning machineutilizing a refrigeration system for the dry cycle of the dry cleaningmachine.

2. Background

The first dry cleaning machines were no more than washer extractors thatused a dry cleaning solvent in place of water and a separate steamheated and water cooled dryer. These machines did not recover theevaporated solvent during the dry cycle and just release it to theatmosphere, which had significant environmental consequences.

The next version of dry cleaning machines had a system vaporizing thesolvent and passing the evaporated solvent over a cooling coil torecover the solvent so that a good portion of the evaporated solventwould be condensed back into the washer.

The next step in the evolution of cry cleaning technology was to conductthe dry cycle in the same machine that was used as the washer extractor.This system was sufficient when perchlorethylene solvents (“perc”) wereused, but there was still a great loss of solvent to the atmosphere.

In order to improve the solvent recovery, a refrigeration unit was addedto the machines where the refrigeration unit is used to cool down thesolvent vapors and allow higher solvent recovery. This system workedfairly well until federal and local agencies determined that “perc”fumes were hazardous and began phasing out these machines.

The alternative solvents that came to the market were basicallyhydrocarbon solvents or their blends, which took longer to clean andwere much harder to dry. The industry tried to use the same dryingtechniques that were in place at the time but the length of time neededfor washing and drying was greater.

Another conventional dry cleaning machine uses an air cooled, heat pumpdrying system with a higher efficiency but has its drawbacks. Themachine tends to be overheated because the air cooling cannot cooledwith high ambient temperatures in the dry cleaning plants and the heatpumps tend to take a long time to build up to running temperature makingthe drying cycle longer.

Also, conventional dry cleaning machines are adopted to use only onekind of solvent within the machines although different kinds of solventsmay be required depending on the load. For example, commonly usedhydrocarbon based solvents are good for garments having leather or metalbeads or losing its color easily.

However, stained garments often require a stronger solvent. In order tochange the solvent, the existing solvent need to be manually purged outfrom the solvent tank and other parts of the machine to prevent thesolvents from being mixed. During the solvent exchange process, theoperator can be exposed to the harmful solvent fume. Due toinconvenience involved in the manual exchange of the solvent with asingle dry cleaning system, often two separate dry cleaning machines areused for different solvents-one for stronger solvent and the other for aweaker solvent.

Accordingly, a new dry cleaning machine solving drawbacks ofconventional dry cleaning machines is desirable.

SUMMARY OF THE INVENTION

According to one embodiment of the invention, a dry cleaning machinewith washing and drying cycles has a rotary drum holding clothing orlikes, a first solvent tank for storing a first solvent, a secondsolvent tank storing a second solvent, a first water separatoroperationally connected to the first solvent tank, a second waterseparator operationally connected to the second solvent tank, and asolvent recovery system operationally connected to the first and secondwater separators and the rotary drum.

The solvent recovery system includes a refrigeration system containing afirst heat exchange system, a second heat exchange system, arefrigeration tank storing a refrigerant, and a fan for cooling therefrigerant.

The washing cycle uses one solvent from either the first or secondsolvent tank at a time and the drying cycle uses heated air to evaporatethe solvent used in the washing cycle. The dry cleaning machine isconfigured on that the first and second solvents can be independentlyused within the same machine for different washing cycles without needof manual exchange of the solvents or system purge.

Thus, in this embodiment, the first heat exchange system heats air to beused for the drying cycle, the second heat exchange system cools andcondenses the solvent evaporated by the heated air. The condensedsolvent passes through the first water separator where water isseparated and is then collected in the first solvent tank if thecondensed solvent is the first solvent. The condensed solvent goesthrough the second water separator and is collected in the secondsolvent tank if the condensed solvent is the second solvent.

In another embodiment according to the invention, a dry cleaning machinehaving a washing cycle and drying cycle includes a rotary drum, a firstsolvent tank for storing a first solvent, a first water separatoroperationally connected to the first solvent tank, a second solvent tankfor storing a second solvent, a second water separator operationallyconnected to the second solvent tank, a first solvent recovery systemoperationally connected to the first water separator and the rotarydrum, a second solvent recovery system operationally connected to thesecond water separator and the rotary drum, and a refrigeration systemwherein the refrigeration system comprises a first heat exchange system,a second heat exchange system, a third heat exchange system, a fourthexchange system, a refrigerant tank for storing a refrigerant, and a fanfor cooling the refrigerant.

The washing cycle uses either the first solvent or the second solvent ata time and the drying cycle uses heated air to evaporate the first orsecond solvent used in the washing cycle.

The first heat exchange system heats air to be used for the drying cyclewhen the first solvent is used in the washing cycle, the second heatexchange system cools and condenses the first solvent evaporated by theair heated by the first heat exchange system, the third heat exchangesystem heats air to be used for the dry cycle when the second solvent isused for the washing cycle, and the fourth heat exchange system coolsand condenses the second solvent evaporated by the air heated by thethird heat exchange system. The first or second solvent passes throughrespectively the first or second water separator and is collected inrespectively the first or second solvent tank.

The dry cleaning machine is capable operating with the first solvent andthe second solvent independently and separately so that potentialcontamination of one solvent with the other is minimized.

In another embodiment according to the invention, a dry cleaning machinehaving a washing cycle and drying cycle includes a rotary drum, a firstsolvent tank for storing a first solvent, a first water separatoroperationally connected to the first solvent tank, a second solvent tankfor storing a second solvent, a second water separator operationallyconnected to the second solvent tank, a third solvent tank for storing athird solvent, a third water separator operationally connected to thethird solvent tank, a first solvent recovery system operationallyconnected to the first and second water separators and the rotary drum,a second solvent recovery system operationally connected to the thirdwater separator and the rotary drum and a refrigeration system whereinthe refrigeration system comprises a first heat exchange system, asecond heat exchange system, a third heat exchange system, a fourthexchange system, a refrigerant tank for storing a refrigerant, and a fanfor cooling the refrigerant. The washing cycle may use one of the first,second and third solvents at a time, and the drying cycle may use heatedair to evaporate the solvent used in the washing cycle.

The first heat exchange system heats air to be used for the drying cyclewhen the first or second solvent is used in the washing cycle, thesecond heat exchange system cools and condenses the solvent evaporatedby the air heated by the first heat exchange system, the third heatexchange system heats air to be used for the dry cycle when the thirdsolvent is used in the washing cycle, and the fourth heat exchangesystem cools and condenses the third solvent evaporated by the airheated by the third heat exchange system.

The condensed first, second or third solvent passes through respectivelythe first, second or third water separator and is collected inrespectively the first, second or third solvent tank, creatingindependent and separate solvent circulations with the machine.

In an embodiment, the dry cleaning machine can have a heat booster whichcan used to heat the air to be used for the drying cycle. The heatenergy for the heat booster can be supplied by using steam received froman external boiler. However, other embodiment according to the presentinvention can have a separate internal heater to supply the heat to theheat booster. The internal heater could be an electrical heater or asmall boiler.

In an embodiment, the dry cleaning machine has a refrigerant coolingsystem, which cools the refrigerant tank when the tank reaches at apreset temperature in order to prevent the machine from shutting down.The refrigerant cooling system can be configured to be turned off whenthe tank reaches at another preset temperature. The temperature of therefrigerant tank means a temperature measured at the tank or atemperature of the refrigerant exited from the tank.

The preset temperature may be about 70-100° F., preferably 80-90° F. Therefrigerant cooling system may include a coolant tank storing a coolant,which is used to cool the refrigerant tank.

The coolant may be cooled by the refrigeration system when the fanprovides sufficient cooling for the refrigerant.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate preferred embodiments withoutshowing many components or structures commonly used in conventional drycleaning machines and can readily understood by one of skill in the artin absence of such components or structures.

FIG. 1 is a schematic diagram illustrating a dry cleaning machineaccording to a preferred embodiment of the present invention where twosolvent tanks and one solvent recovery system are used.

FIG. 2 is a schematic diagram illustrating a dry cleaning machineaccording to another preferred embodiment of the present invention wheretwo solvent tanks and two solvent recovery systems are used.

FIG. 3 is a schematic diagram illustrating a dry cleaning machineaccording to another preferred embodiment of the present invention wherethree solvent tanks and two solvent recovery systems are used.

FIG. 4 is a schematic diagram illustrating a refrigeration systemaccording to a preferred embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating a refrigeration systemaccording to another preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

In FIG. 1, a dry cleaning machine according to a preferred embodiment ofthe present invention is illustrated. The dry cleaning machine includesa solvent recovery system 100, a rotary drum 300 that hold garments tobe dry cleaned, two solvent tanks 601, 602 separately holding twodifferent solvents, two water separators 401, 402, two separate pumps701, 702, at least two filter system 201, 202, a button trap 500. Whengarments are placed in the rotary drum for dry cleaning, a solvent issupplied to the drum from either the solvent tank 601 or 602 dependingon the user's choice or setting.

When the first solvent stored in the solvent tank 601 is selected, thepump 701 transfers the solvent from the solvent tank through the filtersection 201 where the solvent is filtered out impurities including colordyes.

The locations of the pumps shown in the figures are illustration purposeonly, and one of skill in the art would easily optimize the locationsfor better or proper operations of the dry cleaning machine.

The drum 300 is operationally connected to the solvent recovery system100 so that air heated in the solvent recovery system can circulate intothe drum and the solvent evaporated from the drum by the heated air cancirculate into the solvent recovery system where the solvent can becondensed and recovered.

The drum 300 optionally has a button trap 500, which trap heavyimpurities such as buttons during the washing cycle.

The solvent recovery system is operationally and separately connected totwo water separators, 401, 402 which are operationally connected to twosolvent tanks 601, 602 respectively.

The solvent recovery system has a refrigeration system having twoseparate heat exchange systems—one for heating air for the drying cycleand the other for cooling and condensing the solvent evaporated duringthe drying cycle allowing recovery of the solvent. The refrigerationsystem is not illustrated in FIG. 1.

While the two solvents stored in the solvent tanks 601 and 602 circulatewithin the dry cleaning machine through two separate routes, they stillgo through common components such as the rotary drum, the solventrecovery system, and the button trap. A small residual amount of onesolvent from a dry cleaning cycle may become in contact with the othersolvent from another a dry cleaning cycle.

Thus, this system is more suitable where a small amount of the solventscan be mixed without affecting operation of the dry cleaning machine ormaintenance. For example, solvents with chemically the same solvent indifferent concentrations could be used. In a certain situation, twochemically different kinds of solvent may be also used because they maybe chemically comparable or the amount of the first solvent that maycontaminate the second solvent being used in a subsequent dry cleaningoperation may not affect the dry cleaning operation or use of thesolvent for another dry cleaning operation.

For some solvents, however, more complete segregation between theircorresponding dry cleaning cycles may be desirable. A dry cleaningmachine illustrated in FIG. 2 may be more suitable for such a situation.

The dry cleaning machine in FIG. 2 is similar in that there are twoseparate sets of a solvent tank, a water separator, a pump and a filtersystem. But this dry cleaning machine has two separate solvent recoverysystems, 101, 102 which are respectively connected to the two separatesets of a solvent tank (601, 602), a water separator (401, 402), a pump(701, 702) and a filter system (201, 202).

The two solvent recovery systems may have two separate refrigerationsystems but may share a single refrigeration system with extra heatexchange systems. For example, the refrigeration system can have arefrigeration tank, a fan but two separate sets of the heat exchangesystems for two different solvents.

Alternatively, the refrigeration system can have only single set of theheat exchange system but the two solvent recovery systems may have twoseparate chambers separately positioned near the same set of the heatexchange systems so that the heating of air or condensing of the solventcaused by the same set of the heat exchange system. For example, thesolvent recovery systems have coil shape chambers, which round aroundthe same heat exchange system alternatively.

Accordingly, when an embodiment of the present invention is described interms of multiple heat exchange systems for the same purpose, i.e.,heating or cooling, such multiple heat exchange systems includephysically a single heat exchange system or a less number of the heatexchange systems, providing the purported function the same multipletimes as the number of the multiple heat exchange systems.

Different solvents are being used for dry cleaning machines. Hydrocarbon base solvents and silicon base solvents are examples. However,many different solvents can be used. Use of different solvents do notaffect the scope of the present invention.

In FIG. 3, a dry cleaning machine has three solvent tanks 603, 604, 605but two solvent recovery systems 103, 104. In this embodiment, onesolvent recovery system 104 is dedicated to a particular solvent tank605 and the other solvent recovery system 103 is operationally connectedto the other two solvent tanks 603, 604. The dry cleaning machine mayhave three filer systems 203, 204, 205, which are respectively connectedto the three solvent tanks.

The three solvent tank systems may have two separate refrigerationsystems but may share a single refrigeration system with extra heatexchange systems as described with respect to FIG. 2.

In reference to FIG. 4 illustrating a refrigeration system, arefrigerant tank 1 stores a refrigerant, which is cooled by a fan 9,which circulates air over an air condenser 6. A refrigerator compressor5 compresses the refrigerant where the temperature of the refrigerantrises. The heated and pressurized refrigerant is supplied to a heatexchange system 4 to heat air to be used the drying cycle. In anotherheat exchange system 3, the refrigerant evaporates providing a lowertemperature environment. The solvent evaporated during the dry cycle issubjected to the heat exchange system 3 and condensed. An evaporator 2,where the refrigerant also evaporates, may be used to lower thetemperature of the solvent stored in the solvent tanks or the solvent tobe used in the washing cycle.

The fan 9 alone may not be able to cool the refrigerant fast enough,causing the temperature of the refrigerant tank arises. When thetemperature reaches at a critical temperature, the entire refrigerationsystem may shot down. In order to prevent the refrigerant tanktemperature from rising over a critical temperature, a refrigerantcooler system may be provided around the refrigerant tank 1.

A refrigerant cooler system may use a coolant or the dry cleaningsolvent to cool the tank. The coolant may be stored in a separatecoolant tank 38, 38 a. The coolant in FIG. 5 may be cooled by anevaporator 2 a.

Water can be used as a coolant, which may be provided from an externalwater supply without a separate water tank.

The refrigerant cooling system may be configured to be turned on when atemperature reaches at a predetermined temperature. The predeterminedtemperature may be about between 70-100° F., preferably 80-90° F.

The heated air for the drying cycle can be further heated with anassistance of a heat booster 7. The heat energy required by the heatbooster in heating the air may be supplied by an external source viasteam as shown in FIG. 5.

The dry cleaning machines illustrated in FIG. 4 contains an internalheating source 10 for the heat booster such as an electrical heater. Theheater can directly heat the heat booster or supply hot steam to theheat booster.

The term “solvent” used herein means a single solvent or a mixture oftwo or more solvents. The term “different solvents” describes where thesolvents are different in their concentrations, chemical compositions orboth.

While a number of exemplary aspects and embodiments have been discussedabove, those of skill in the art will recognize certain modifications,permutations, additions and sub-combinations thereof. It is thereforeintended that the following appended claims and claims hereafterintroduced are interpreted to include all such modifications,permutations, additions and sub-combinations as are within their truespirit and scope.

What is claimed is:
 1. A dry cleaning machine having a washing cycle anda drying cycle, comprising: a rotary drum; a first solvent tank forstoring a first solvent; a first water separator operationally connectedto the first solvent tank a second solvent tank for storing a secondsolvent; a second water separator operationally connected to the secondsolvent tank; and a solvent recovery system operationally connected tothe first and second water separators and the rotary drum, the solventrecovery system comprising a refrigeration system wherein therefrigeration system comprises a first heat exchange system and a secondheat exchange system, a refrigerant tank for storing a refrigerant, anda fan for cooling the refrigerant, wherein the washing cycle uses eitherthe first solvent or the second solvent at a time and the drying cycleuses heated air to evaporate the solvent used in the washing cycle; andwherein the first heat exchange system heats air to be used for thedrying cycle; the second heat exchange system cools and condenses thesolvent evaporated by the heated air; the condensed solvent passesthrough the first water separator and is collected in the first solventtank when the condensed solvent is the first solvent and the condensedsolvent passes through the second water separator and is collected inthe second solvent tank when the condensed solvent is the secondsolvent.
 2. The dry cleaning machine according to claim 1, furthercomparing a heat booster heating the air to be used for the dryingcycle.
 3. The dry cleaning machine according to claim 2, furthercomprising an electrical heater providing heat energy for the heatbooster.
 4. The dry cleaning machine according to claim 2, wherein heatenergy for the heat booster is provided by an external heat source usingsteam.
 5. The dry cleaning machine according to claim 1, furthercomprising a refrigerant cooling system wherein the refrigerant coolingsystem is turned on when the refrigerant tank reaches at a presettemperature.
 6. The dry cleaning machine according to claim 5, whereinthe preset temperature is between about 70-100° F.
 7. The dry cleaningmachine according to claim 5, further comprising a coolant tank storinga coolant wherein the refrigerant cooling system utilizes the coolant tocool the refrigerant tank.
 8. A dry cleaning machine having a washingcycle and a drying cycle, comprising: a rotary drum; a first solventtank for storing a first solvent; a first water separator operationallyconnected to the first solvent tank a second solvent tank for storing asecond solvent; a second water separator operationally connected to thesecond solvent tank; a first solvent recovery system operationallyconnected to the first water separator and the rotary drum, a secondsolvent recovery system operationally connected to the second waterseparator and the rotary drum; and a refrigeration system wherein therefrigeration system comprises a first heat exchange system, a secondheat exchange system, a third heat exchange system, a fourth exchangesystem, a refrigerant tank for storing a refrigerant, and a fan forcooling the refrigerant, wherein the washing cycle uses either the firstsolvent or the second solvent at a time and the drying cycle uses heatedair to evaporate the solvent used in the washing cycle; and wherein thefirst heat exchange system heats air to be used for the drying cyclewhen the first solvent is used for the washing cycle; the second heatexchange system cools and condenses the first solvent evaporated by theair heated by the first heat exchange system; the third heat exchangesystem heats air to be used for the dry cycle when the second solvent isused for the washing cycle, the fourth heat exchange system cools andcondenses the second solvent evaporated by the air heated by the thirdheat exchange system; the first or second solvent passes throughrespectively the first or second water separator and is collected inrespectively the first or second solvent tank.
 9. The dry cleaningmachine according to claim 8, further comparing a heat booster heatingthe air to be used for the drying cycle.
 10. The dry cleaning machineaccording to claim 9, further comprising an electrical heater providingheat energy for the heat booster.
 11. The dry cleaning machine accordingto claim 9, wherein heat energy for the heat booster is provided by anexternal heat source using steam.
 12. The dry cleaning machine accordingto claim 8, further comprising a refrigerant cooling system where therefrigerant cooling system is turned on when the refrigerant tankreaches at a preset temperature.
 13. The dry cleaning machine accordingto claim 12, wherein the preset temperature is between about 70-100° F.14. The dry cleaning machine according to claim 8, wherein the firstsolvent is a hydrocarbon base solvent and the second solvent is asilicon base solvent.
 15. The dry cleaning machine according to claim 8,further comprising a third solvent tank holding a third solvent and athird water separator, the third water separator being operationallyconnected to the first solvent recovery system and the third solventtanks.
 16. A dry cleaning machine having a washing cycle and a dryingcycle, comprising: a rotary drum; a first solvent tank for storing afirst solvent; a first water separator operationally connected to thefirst solvent tank a second solvent tank for storing a second solvent; asecond water separator operationally connected to the second solventtank; a third solvent tank for storing a second solvent; a third waterseparator operationally connected to the third solvent tank; a firstsolvent recovery system operationally connected to the first and secondwater separators and the rotary drum, a second solvent recovery systemoperationally connected to the third water separator and the rotarydrum; and a refrigeration system wherein the refrigeration systemcomprises a first heat exchange system, a second heat exchange system, athird heat exchange system, a fourth exchange system, a refrigerant tankfor storing a refrigerant, and a fan for cooling the refrigerant,wherein the washing cycle uses one of the first, second and thirdsolvents at a time and the drying cycle uses heated air to evaporate thesolvent used in the washing cycle; and wherein the first heat exchangesystem heats air to be used for the drying cycle when the first orsecond solvent is used for the washing cycle; the second heat exchangesystem cools and condenses the solvent evaporated by the air heated bythe first heat exchange system; the third heat exchange system heats airto be used for the dry cycle when the third solvent is used for thewashing cycle, the fourth heat exchange system cools and condenses thethird solvent evaporated by the air heated by the third heat exchangesystem; the condensed first, second or third solvent passes throughrespectively the first, second or third water separator and is collectedin respectively the first, second or third solvent tank.
 17. The drycleaning machine according to claim 16, further comparing a heat boosterheating the air to be used for the drying cycle.
 18. The dry cleaningmachine according to claim 17, further comprising an electrical heaterproviding heat energy for the heat booster.
 19. The dry cleaning machineaccording to claim 16, further comprising a refrigerant cooling systemwhere the refrigerant cooling system is turned on when the temperatureof the refrigerant tank reaches at a preset temperature.
 20. The drycleaning machine according to claim 16, wherein the first and secondsolvents are hydrocarbon base solvents and the third solvent is asilicon base solvent.